1. Field of the Invention
The invention relates to a method of manufacturing metallic layers and somewhat more particularly to a method of reproducibly manufacturing metallic layers for semiconductor and thin film technology.
2. Prior Art
Extremely high requirements are made for tolerance and constancy in electrical properties of metallic layers utilized in semiconductor and thin film technologies. The temperature coefficient of electrical resistance of, for example, a thin film resistor composed, for example, of chromium-nickel, aluminum-tantalum or tantalum-oxynitride (TaO.sub.x N.sub.y) can only amount of a few 10.sup.-6.sub.K.sup.-1. Further, the resistance value of such layers, which often are only 10 nm thick, can only change by a few percentage points over many years.
A further example of the high property requirements of metallic layers utilized in semiconductor and thin film technology is in the manufacture of .beta.-tantalum layers which are required for certain thin film capacitors. This structural modification of .alpha.-tantalum only occurs in thin layers when very specific nucleus formation and growth conditions are provided. In order to be able to controllably manufacture such layers, neither the composition nor the structure nor the texture of the layer can vary.
Such extremely high property requirements make it necessary to follow and, if necessary, control layer growth, practically beginning with a first mono-atomic layer.